Except this is not only about Fireball and whether or not it might have a DC a few points lower.
It's about Clerics / Paladins / Bards / Warlocks / whoever dipping into Wizard to get their stuff, if it's being made easier. Misty Step. Mirror Image. Cloud of Daggers. Detect Thoughts. Disguise Self. Fly. Stoneskin. Counterspell.
Not everything has a DC. And I have a feeling they are making this theft very easy to do.
Yep, sounds like they are depending on action economy to handle balance.
